Application programs that execute on computing devices and computer networks may require the use of services provided by other physical or logical devices connected to the computing device or network. Presently, application programs use a wide range of application programming interfaces (APIs), protocols, and object models to discover, enumerate, and describe services and devices on a local computing device or across a plurality of devices in a computer network. The mechanisms available to discover, enumerate, and describe services and devices differ significantly, even when the services and devices involved are conceptually similar.
For example, consider a situation in which an application seeks to enumerate available printers. When executing within an administered, corporate environment, the application may need to use Lightweight Directory Access Protocol (LDAP) to communicate with a Microsoft Active Directory® directory service store to discover registered corporate printers, NetBT to discover print queue servers, and Bluetooth to discover personal area network printers. In addition, the application might have to invoke device management APIs to discover direct attached printers, and UPnP™ APIs to discover UPnP printers. Each of these mechanisms requires understanding of a particular API, protocol, and query semantic.
The number of APIs and protocols required to for an application to discover, enumerate, and describe services complicates the task of software development.